Foot Disorders Database

The terms fallen arches and flat feet are used interchangeably to refer to a condition in which there is no arch of the foot. An arch is formed by tendons in the foot that stretch from the heel of the foot to the base of the toes, or metatarsals. There are also supporting tendons that originate in the lower leg. Together, these tendons work to form an arch, noticeable as a slight rise in the inner midsole of the foot. This rise or arch can be classified as a normal arch, a high arch, or a fallen arch. When tendons do not work together to pull properly, this results in a fallen arch or flat foot. Aside from the occasional pain associated with flat feet, problems with fallen arches can extend upwards to the ankles, knees, hips, and even the back, altering the biomechanics of the body.

Causes

A fallen arch occurs because one of the main structures that support the arch has broken or torn. Usually it occurs without trauma, although a small injury associated with the onset of the pain is often recalled, it is sometimes difficult to determine whether the injury was clearly big enough to permanently injure the leg. I suspect that even before the symptoms that the structure that broke was weakening and the injury was simply the ?needle that broke the camels back?. The structure that is most commonly torn is the posterior tibial tendon. This tendon is attached to a muscle on the inside of the back of the ankle, and runs along the medial malleolus, the bony prominence on the inside of the ankle, to attach to a bone in the arch called the navicular bone. It usually begins to weaken and stretch along the back of the medial malleolus. It often begins as a swelling and the arch flattens over the next several weeks to months. As the arch flattens, other structures that support the arch begin to stretch and tear. The bones along the outside of the ankle begin to crush together, causing pain and swelling in this are, and the toes may tilt to the outside as the arch collapses. It is not known why this process begins. It is often associated with diabetes and rheumatoid arthritis and other inflammatory diseases. It also is more common as a person enters the fifty to seventy year age range. ?Fallen arches? are much more common in people who are already flat footed.

Symptoms

It?s possible to have fallen arches and experience no symptoms whatsoever. But many people do notice some problems with this condition. Their feet, back and legs ache. Standing on their toes is difficult, if not impossible, and they note swelling around the arch and heel.

Diagnosis

An examination of the foot is enough for the health care provider to diagnose flat foot. However, the cause must be determined. If an arch develops when the patient stands on his or her toes, the flat foot is called flexible and no treatment or further work-up is necessary. If there is pain associated with the foot or if the arch does not develop with toe-standing, x-rays are necessary. If a tarsal coalition is suspected, a CT scan is often ordered. If a posterior tibial tendon injury is suspected, your health care provider may recommend an MRI.

Some of the aspects of the pain with a ?fallen arch? are related to the crushing of the joints of the outside of the foot and from the stretching of ligaments and tendons of the inside of the foot. Unfortunately, some parts of the damage from the fallen arch, the weakness in the tendons and the new shape of the foot, are not correctable without surgical reconstruction. The first goal is to stabilize the collapsed arch. This can be done through braces. If the deformity is mild, an over-the-counter arch support may be sufficient. In more severe deformities an hinged or solid ankle brace may be necessary. Rehabilitative exercises under the supervision of a physical therapist will help increase the strength of the remaining muscles. Stiffness of certain tendons including the Achilles and hamstring is also very helpful as tightness in these structures is very common in people with ?fallen arches?. Postural training is necessary. A short period of casting or walking in a cast boot will improve swelling of a recent partial tear of the tendons and ligaments on the inside of the ankle. Nonsteroidal anti-inflammatory medications such as ibuprofen, and naprosyn can help to relieve the pain, but do not heal the injuries associated with this or decrease the swelling significantly. Surgical reconstruction is available if the pain cannot be controlled reasonably with these measures.

Surgical Treatment

Procedures may include the following. Fusing foot or ankle bones together (arthrodesis). Removing bones or bony growths, also called spurs (excision). Cutting or changing the shape of the bone (osteotomy). Cleaning the tendons' protective coverings (synovectomy). Adding tendon from other parts of your body to tendons in your foot to help balance the "pull" of the tendons and form an arch (tendon transfer). Grafting bone to your foot to make the arch rise more naturally (lateral column lengthening).